Spring action oscillator



July 14, 1970 H. MEYER 3,520,127

SPRING ACTION OSCILLATOR Filed Aug. 1, 1968 ted P tent 3,520,127 Patented July 14, 1970 3,520,127 SPRING ACTION OSCILLATOR Hans Meyer, Bugnon 24, Renens, Switzerland Filed Aug. 1, 1968, Ser. No. 749,452 Claims priority, application Switzerland, Aug. 2, 1967, 10,892/ 67 Int. Cl. G04c 3/04 US. Cl. 58-43 8 Claims ABSTRACT OF THE DISCLOSURE A spring action oscillator has a steady frame and at least one oscillating member, as well as springs arranged radially to the oscillating member, which springs are secured by one of their ends to the frame and engage the oscillating member with the other end. The springs are of such shape that, within the range of useful oscillatory amplitudes, at the location of their points of contact with the oscillating member, they move along a circular arc, the center of which is located on the axis of rotation of the oscillating member.

Spring action oscillators are used as frequency-controlling elements in oscillatory circuits which, in turn, control mechanisms such as clocks, timers and the like.

It is well known that, for instance, clocks are provided with oscillators which consist of a balance cooperating with a spring, the oscillations of which are sustained by another spring. The disadvantages of such oscillatory systems are known. Bearing friction and bearing slackness restrict their efficiency factor to a comparatively low value. It has, therefore, already been proposed to eliminate both these detrimental effects by having the balance supported by a system of radially arranged springs which originate from the center of rotation (for instance as disclosed in the US. Pat. No. 2,939,971). This solution, involves other disadvantages: in addition to the fact that an oscillator of the same size as the one described introductorily oscillates at a much greater speed, there arise during the oscillation not only rotary oscillations but also transverse oscillations in the spring spokes, which are superimposed on and interfere with the former ones. Further, due to the comparatively stiff spring system, the amplitude of oscillation is restricted to comparatively very low values, so that the practicability seems to be questionable.

The invention has for its object to eliminate the abovementioned disadvantages. It relates to a spring action oscillator which consists of a steady frame and of at least one oscillating member, as well as of springs arranged radially to the oscillating member, which springs are secured by one of their ends to the frame and engage the oscillating member with the other end, wherein the springs are such shape that, within the range of useful oscillatory amplitudes, at the location of their points of contact with the oscillating member, they move along a circular arc, the center of which is located on the axis of rotation of the oscillating member.

Owing to these measures, no transverse stresses can occur in the oscillator Within a useful range of amplitude, which is comparatively wide. Since no further moments are applied at the end of the springs which engage the oscillating member, the frequency of oscillation, for the same spring length, will be lower in the oscillator according to the invention than in the heretofore described oscillators, which again facilitates the further transmission of the oscillations.

The ratio of the mass of the oscillating member to that of the frame is of importance to the quality of the oscillatory system, that is to say the mass of the frame should be as large as possible while that of the oscillating member should be as small as possible. Even if this can be satisfactorily achieved in many practical applications, there are however fields of application in which these requirements cannot be satisfied. Therefore, embodiments of the invention will be described in which two oscillators are coupled together so as to eliminate interaction with the frame. Thereby the application of the principle of the invention is also possible with frame having a small mass.

The inventive concept is disclosed with reference to the attached drawing, wherein:

FIG. 1 shows an oscillatory system;

FIG. 2 is a section through FIG. 1, along the line FIG. 3 is a diagrammatic view of an oscillator having three spring elements;

FIG. 4 is a diagrammatic view of an oscillatory system having two oscillators arranged side by side; and

FIG. 5 is a diagrammatic view of an oscillatory system having two superposed oscillators.

FIGS. 1 and 2 show a frame 1 with a bottom plate 1a and an oscillating member 2. The oscillating member 2 is connected to the frame 1 by springs 3 and 4 inserted in the oscillating member 2 and secured to the frame 1 by plates 5 and screws 6. The two springs 4 have together the same width as the spring 3 so that the two spring elements arranged perpendicular to each other have the same bending resistance. The springs 3 and 4 may, for instance, be secured to the oscillating member 2 by calking, screwing, soldering, or the like.

In the oscillator being described, the oscillating member is carried by the springs 3 and 4. As shown in FIG. 1 the oscillating member 2 has a center of gravity which substantially coincides with its axis of oscillation and the springs 3 and 4 intersect at said axis. According to the inventive concept the oscillating member could also be carried in separate bearings (for instance on a compressed-air bearing) and the springs could engage the oscillating member by a rigid or a flexible mounting. The oscillating member 2 is provided with two cams 2a which cooperate with a magnet consisting of a yoke 11 and coils 12. This magnet ensures in a manner known per se, in connection with a control system not shown on the drawing, that the oscillator continuously receives energy suflicient to keep its amplitude at a constant value. A spring catch 7 fastened to the oscillating member by a screw 8 operates a ratchet wheel 9 mounted on a shaft 10 which drives a gearing not shown on the drawing. It is obvious that the impulses delivered by the oscillator can also be transmitted in any other manner known in the art, for instance in that the electric switching impulses generated in the magnet system are converted into driving impulses.

In order to simplify the diagrammatic representations, known elements used in oscillators, such as balancing elements, have been omitted.

The materials from which the oscillator is constructed are suitably chosen so that the frequency generated is maintained independently of temperature changes.

The springs 3 and 4 are prism shaped. Their free length is such that it corresponds to the expression wherein, L refers to the free length of the spring and R to the radius of the oscillating member 2 in FIG. 1. Therefore, the end of the springs connected to the oscillating member 2 follow, when being deflected, circular arcs with a center M and a radius R, that is to say that the ends of the springs follow without coercion the rotary motion of the oscillating member 2. This behavior is true for a comparatively wide angular deflection of the oscillating member 2, i.e. about i5, so that the available amplitude of oscillation is sufficient for practical applications. 4

The inventive concept is not restricted to the use of prism-shaped springs; with a suitable modification of the ratio L/R other spring shapes may also be used to embody the proposed principle.

For the calculation of the oscillatory frequency, the springs 3 and 4 of the device described can, in practice, be considered as unilaterally clamped springs, the other end of which is freeloaded. Thus is derived the advantage of smoother operation than that provided in the oscillatory system with spring spokes mentioned in the preamble, that is to say a lower oscillatory frequency, so that a simpler secondary drive can be obtained for the same structural size.

In FIGS. 1 and 2, the oscillating member 2 is provided with two spring elements 3 and 4 crossed at right angles. For extreme requirements, the number of spring elements may be increased. FIG. 3 shows diagrammatically by way of example an oscillating member 20 provided with three spring elements 22, the springs of which are secured to frame arms 21 by plates 23 and screws 24.

The ratio of the mass of the oscillating member to that of the frame is of importance to the oscillatory chajracteristics of the system. If for engineering reasons this ratio cannot be given a value high enough (i.e. when the frame is too light in relation to the oscillating member), it is advisable to select an oscillatory system consisting of two oscillators which oscillate in opposed directions. In FIG. 4, for instance, two oscillators are arranged side by side. Their oscillating members 30 are connected to the arms 31 of a common frame by springs 32 secured by means of plates 37 and screws 38. A magnet system 33, 34 ensures that the oscillations are sustained in both oscillators. Cams 35 and 36, which may only touch each other at the start of movement, ensure that the oscillators oscillate in opposed directions.

In the oscillatory device shown in FIG. 4, the mass of the frame has no influence on the oscillatory characteristics of the system, since the torques originated in the oscillators neutralize each other. The same eifect can also be obtained by arranging the two oscillators coaxially (FIG. In this case care should be taken that the oscillating members 40 which are articulated on the frame 41, 41a by springs not shown on the drawing, oscillate in opposed directions.

I claim:

1. A spring action oscillator comprising a stationary frame, at least one vibrating oscillating member having a center of gravity substantially coinciding with the axis of oscillation thereof, at least two elongated springs respectively secured at one end to the frame and the other end to the oscillating member to support the oscillating member, said springs being disposed to cross one another at said oscillation axis of said oscillating member, said springs being secured to said frame on one side of said oscillation axis, and to said oscillating member on the opposite side of said oscillation axis, the length of said springs being such that at the securing point to the oscillating member substantially no stress due to bending take place.

2. A spring action oscillator according to claim 1 wherein the springs are prism shaped and their length is equal to 1.5 times the value of the radius of the circular arc along which their connection points with the oscillating member move.

3. A spring action oscillator according to claim 1 wherein the springs are arranged perpendicular to each other.

4. A spring action oscillator according to claim 1 said frame and said springs carrying two of said oscillating members arranged side by side and oscillating in opposite directions.

5. A spring action oscillator according to claim 4 wherein the oscillating members include elements which by meshing with each other determine the direction of the oscillation.

6. A spring action oscillator according to claim 4 comprising a common magnet system for driving said oscillating members.

7. A spring action oscillator according to claim 1 said frame and said springs carrying two of said oscillating members in coaxial arrangement and oscillating in opposite directions.

8. A spring action oscillator according to claim 1 wherein said oscillating member is annular and surrounds said frame, said springs being enclosed within said oscillating member.

References Cited UNITED STATES PATENTS 2,679,722 6/ 1954 Kohlhagen. 2,954,701 10/ 1960 Berill 74126 3,318,087 5/1967 Favre.

MILTON KAUFMAN, Primary Examiner US. Cl. X.R. 74126; 3l037 

